Devices within close proximity of each other may wirelessly transfer energy for various reasons. For instance, a device may wirelessly charge another device's battery. Also, two devices may engage in near field communications (NFC).
Such wireless energy transfer may involve an electromagnetic coupling between proximate coils. For example, a first device may have a transmitting coil and a second device may have a receiving coil. When an electrical current flows through the transmitting coil, a magnetic field is generated. In turn, this magnetic field may induce an electrical current in the receiving coil.
Unfortunately, conventional coils are not directional. This may impair the effectiveness of such energy transfer.